What is this a sympton of?

These upper leaves are "rolling up". They started doing it 2 days before getting their first nuts (1/2 strength). I can't say they rolled up any worse after the watering - they just kept rolling (curling inward) at about the same rate.

This is a Mekong High - none of the other strains are doing it and they're all on about the same watering schedule. I've had them on 24/7 lighting. First 2 1/2 weeks were fluorescent & the past 2 have been LED. I guess two of them are essentially going into veg (?).

All I know is this trend of the leaves curling inward can't be good; any thoughts much appreciated.




Edit: In case the image is too small to tell, only the top tier of leaves are doing this.
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i'm wondering if its heat from the lights or other source above the plant?

I just measured & they lights are 7" away from the top leaves. I can't feel any heat from the LED's at all at the level where the leaves are. I was keeping the lights as close as I thought safe to keep an already leggy strain from getting stretched even more.

So even though I can't feel any heat - is it possible the lights are still too close?




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The top leaves are flat again this a.m., but now the middle layer of leaves are curled in exactly like the tops were. But she grew half an inch overnight!

I pulled the lights up to 18" yesterday and this a.m. the middle layer is still curled in. Can't be too much nuts damk, as stated they curled before I added the first round of nuts and it was 1/2 strength. Room temp stays 77°.

Just did a ph test - I only have the cheapo rapitest capsule testers where you mix the soil with the powder and water - it matches the coclor of the "7.0 Nuetral" swatch, so I guess the ph is at least pretty close to good.

Any other ideas anyone? I can put up another pic if it will help showing the curl and where it is now compared to a couple days ago.





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